The web has been around for a while, since it's invention by Tim Berners-Lee in 1989.Since the inception of the web we've had three(3) different versions and these versions have been classified based on how users of the web interact with it.
Web 1.0 was a static kind of web where content was rendered for users to read and it was difficult for users to interact with it.
Web 2.0 is the web of the present, with the arrival of web 2.0, users of the web could now interact with the web. The web was now dynamic and with it came different use-cases we see nowadays like social media, e-commerce e.t.c
Web 3.0 brings a new dimension of decentralization to the web. As successful as web 2.0 was, it was very centralized in nature and was built on top of centralized entities like google, amazon, facebook e.t.c. The centralized structure of web 2.0 enabled these centralized entities to abstract most of the value of the internet for themselves. With Web 3.0 which is built on top of blockchain technology, the internet will be decentralized and each entity that participates have authority over their content.
Web 3 is Open i.e every software is open to the outside world
It will allow participants to interact publicly or privately without any trusted third party.
Neither users nor suppliers need any authorization from a governing body for participating.